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Engineering Failure? Why the Concorde Crashed

On July 25, 2000, an airplane crashed near Paris France. But it wasn’t just any airplane. It was flight 4590, a famous supersonic Concorde. In the following months, investigators concluded that the crash was caused by two things: a strip of metal on the runway and a design flaw regarding the Concorde’s fuel tanks.

A few minutes before the Concorde, another airplane shed a piece of metal onto the runway during takeoff. The Concorde, as it gathered speed, ran over the chunk of metal and blew a tire. Rubber shards from the tire punctured a fuel tank, which caused fuel to gush out. The fuel came into contact with wiring in the Concorde’s landing gear and caught fire, causing the failure of one engine and the Concorde’s subsequent loss of control.

Concluding that a single piece of metal destroyed the multimillion-dollar airplane and killed over 100 people, the investigators blamed the Concorde’s design for inadequate shielding on the fuel tanks. However, in reality, the Concorde’s engineers are most likely not to blame.

The Concorde itself was quite an engineering feat, capable of crossing the Atlantic in just three and a half hours at double the speed of sound. To make this possible, engineers needed to design multiple unique and innovative systems just for the Concorde. Among them were delta wings, four massive engines with afterburners, and sharp nose that tilted down for takeoff and landing. But breaking the sound barrier required more than aerodynamics and power. The engineers used a combination of physics and innovative computer controls to make the Concorde not only a reliable airplane but a safe one.

One unique challenge they solved was the balance of the plane. Upon entering supersonic speeds, the Concorde’s center of balance would shift. To solve this problem, engineers devised a pumping system to balance the plane by pumping fuel to and from various tanks. An innovative computer system displayed the status of each fuel tank and controlled the pumps.

Image Credit: heritageconcorde.com

Computers also controlled another vital system in the Concorde: the air intakes for each of the four massive engines. At top speed, the air flowing around the Concorde’s body could travel at twice the speed of sound or more relative to the airplane. If the air entered the engines at such speeds, the engines would explode. So, the Concorde’s engineers conceived a dual-action air intake, which would slow down the air to a safe speed by generating shock waves. Onboard computers meticulously monitored the system and were even capable of shutting it down in the event of a failure.

Image Credit: concordesst.com

The investigators’ conclusion that the crash was caused by a simple blown tire testifies to the quality of the Concorde’s much more complex mechanical systems, none of which appear to have caused the crash in any way. 

So if the engineering of the plane didn’t cause the crash, what did? The answer comes down to a series of avoidable mistakes on flight 4590.

The most obvious mistake came from the previous flight, which had shed the small piece of metal onto the runway. The strip of metal was titanium, a material known to be dangerous to airplane tires and not recommended by the manufacturer of the airplane. Had the strip been the correct aluminum or stainless steel, the disaster might not have happened.

Furthermore, extra baggage had been added to the Concorde’s cargo bay, resulting in a total weight of 186 metric tons, a ton more than the maximum weight the Concorde was certified to carry. Under normal conditions, the 0.5% deviation might not have been significant, but the conditions weren’t normal. Records indicated an eight-knot tailwind at the time of takeoff, conditions which stipulated that the Concorde should only be carrying 180 metric tons. Flight 4590 was a whole six metric tons outside the engineers’ specifications.

Another avoidable mistake occurred with the Concorde’s maintenance. In routine maintenance on the landing gear, technicians forgot to replace a metal spacer that kept the wheels properly aligned. Resulting misalignment conspired with the blown tire to send the Concorde down the runway in an uncontrollable skid. This forced the pilot to pull the Concorde, which by this point was on fire, off the ground before reaching normal takeoff speed, in order to avoid colliding with another aircraft.

The final error, however, occurred when the burning Concorde was already in the air. The crew shut down engine two on the left side. At that point, the fire appeared to have disabled engine one, so shutting down engine two on the same side left the overweight Concorde with only two engines and no hope of staying in the air long enough to land safely.

Therefore, a series of avoidable mistakes, not an engineering failure, caused the Concorde to crash in 2000. Though the same cannot be said for every disaster, the Concorde was really a groundbreaking and safe piece of engineering.

 

 

 

WORKS CITED

 

“Continental Blamed over Concorde.” BBC News, 6 Dec. 2010, www.bbc.com/news/world-europe-11923556.

Lewis, Robert. “Air France Flight 4590 | Background & Facts.” Encyclopædia Britannica, 18 July 2018, www.britannica.com/topic/Air-France-flight-4590.

Rose, David. “Concorde: The Unanswered Questions.” The Guardian, 13 May 2001, www.theguardian.com/world/2001/may/13/davidrose.focus.

 

Bramson, Dara. “The Concorde: A Supersonic Airplane Too Advanced to Survive.” The Atlantic, July 2015, www.theatlantic.com/technology/archive/2015/07/supersonic-airplanes-concorde/396698/.

 

John Britton. “Concorde Chief Engineer Describes What Made the Supersonic Aircraft Fly.” Aerospace Engineering Blog, 11 Feb. 2018, aerospaceengineeringblog.com/aero-podcast-5-concorde-chief-engineer-john-britton-on-supersonic-flight/.

 

“Concorde: The Real Reason Why the Supersonic Passenger Jet Failed.” Interestingengineering.com, Concorde: The Real Reason Why the Supersonic Passenger Jet Failed, 12 Feb. 2019, interestingengineering.com/concorde-the-real-reason-why-the-supersonic-passenger-jet-failed.

 

de Sausmarez, Steve, Et al. “Concorde Fuel System General.” Heritage-Concorde, www.heritageconcorde.com/fuelgeneral. Accessed 26 Nov. 2020.

 

“ThinkReliability.” ThinkReliability, 2010, www.thinkreliability.com/case_studies/crash-of-the-concorde/.

4 Comments

  1. OliverMunzer/omunzer

    extremely interesting!!!

  2. Woah…. I feel so smart after reading that. Great job Ethan!

  3. Great work very persuasive

  4. This was fascinating Ethan! You explained everything so clearly and made all the technical terms (that normally confound me) engaging and very easy to understand 🙂